Tính ​\(\begin{aligned} &\frac{2}{x+3}-\frac{3}{3-x}+\frac{2-5 x}{x^{2}-9} \end{aligned}\)

* Hướng dẫn giải

 \(\begin{aligned} &\frac{2}{x+3}-\frac{3}{3-x}+\frac{2-5 x}{x^{2}-9}=\frac{2}{x+3}+\frac{3}{x-3}+\frac{2-5 x}{x^{2}-9} \\ &=\frac{2(x-3)+3(x+3)+2-5 x}{(x+3)(x-3)}=\frac{2 x-6+3 x+9+2-5 x}{(x+3)(x-3)}=\frac{5}{(x+3)(x-3)} \end{aligned}\)